It's rare for major state-funded modern art museums to give themselves over to the practioners of one of the undoubted modern art forms of the 20th century, cinema. But the new show at the Centre Pompidou is devoted entirely to the Iranian and Spanish auteurs Abbas Kiarostami and Victor Erice respectively.

Moreover, it is more than a simple joint retrospective of their works (although they are programmed in their entirety too, through the six-month life of the exhibition, which opened this week and runs until January). Instead, the format takes the somewhat gimmicky conceit of a "correspondence" between the two artists - in digital video form.

So far 10 of these short 'letters' have been made and sent, with Erice "posting" the first back in April 2005, and the most recent shot in May of this year. The films vary in length from two and a half minutes to just under half an hour, and frequently pay knowing homage to each others' work - although the two had only met once, briefly, at a film festival, before the joint commission from the Pompidou and Barcelona's Centre for Contemporary Culture.

This somewhat tricksy format probably better suits Kiarostami, whose recent work has become ever more simple, short, pared down and spare - as anyone who saw his 2003 masterpiece Five will testify.

One of the highlights of the show is his new piece, Looking at Tazieh, filmed at a traditional Iranian mourning ceremony, and projected simultaneously on to three gigantic screens. Six 400-seat capacity screenings at the Pompidou have so far been a sell out.

Also on show are a selection of Kiarostami's still photography of roads and landscapes, shown in London three years ago, and his "make-believe" digital forest installation which was briefly on display in the Victoria & Albert museum two years ago.

Victor Erice is a first-rate film-maker. Anyone pitted against Kiarostami, whom many would argue is the greatest living visionary poet in cinema, would suffer. And Erice suffers - his framed spot-lit photos of paintings look weak compared with Kiarostami's half of the gallery, but his freshly-coined paean to the lure of cinema, a 30-minute documentary called The Red Claw, which endlessly revisits, in a swooping, looping, investigation Erice's first experience of cinema - seeing Basil Rathbone as Sherlock Holmes in war-torn 40s Spain - is well-worth catching for its meditation on film, cinema-going, acting and identity.

Both directors' customary gaze is to contemplate human activity within a seemingly omniscient mise en scene, as concerned with place, time and landscape as it is with human interplay. It's thus strangely disconcerting to be oneself confronted by both mens' stare on entering the Pompidou show. Filmed separately but symmetrically, and at diametrically opposing angles and projected on to two giant screens, Kiarostami and Erice stare down the gallery visitor... before turning and heading off in separate directions.